This invention relates generally to a grinding machine and more specfically to an improved loading apparatus which is utilized to sequentially transport a plurality of workpieces to a work area in a grinding machine.
There are many known devices for transporting workpieces to a work area. Some of these known devices include loading wheels which are driven by mechanisms which may be either relatively complicated or difficult to fabricate. Thus, the loading device disclosed in U.S. Pat. No. 2,137,644 utilizes a Geneva drive arrangement to rotate a loading wheel. A swastika wheel is utilized in association with a discharge chute.
A different type of loading wheel drive is disclosed in U.S. Pat. No. 2,433,717. The loading wheel disclosed in this patent is indexed by a stripping mechanism of the ratchet and pawl type. The loading wheel is loaded on its underside and the finished workpieces are discharged at the top of the wheel. As the workpieces enter the wheel, they are held against loading blocks by a belt which encircles most of the wheel. This belt also functions to rotate the workpieces in the loading blocks during a grinding operation.
Another apparatus utilizing a Geneva mechanism to index a loading wheel is disclosed in U.S. Pat. No. 2,805,524. During operation of the loading apparatus disclosed in this patent, the loading wheel is indexed to present workpieces to the grinding zone where they are picked up magnetic chucks. The loading wheel then moves away from the grinding or work zone while the workpiece is ground. After the workpiece has been finished, the loading wheel moves back into the grinding zone and picks up the finished workpiece and the wheel is indexed to place another workpiece in the grinding zone.
A wheel for loading workpieces into a grinding machine is also disclosed in U.S. Pat. No. 3,073,074. This loading wheel includes a pair of disks which are mounted on a shaft. Each of the disks has work engaging notches in its periphery to support workpieces and move them from an input location to a grinding location and then from the grinding location to an exit chute. To effect rotation of the grinding wheel, an index ring attached to the grinding wheel is rotated by an oscillating disk having a plunger which engages the index ring. Mounted between the two disks of the loading wheel is a sizing control sensor which is moved into and out of engagement with the workpiece.
Still another indexable loading wheel is disclosed in U.S. Pat. No. 3,309,821. This loading wheel is utilized to transport workpieces from an infeed chute to a grinding zone and then to transfer finished workpieces to an output chute. Equally spaced work supports in the periphery of the loading wheel are adjustable so as to carry different sizes of workpieces. The output shaft of a hydraulic motor is rotated to index the wheel. This output shaft rotation is transferred to the loading wheel through a gear train.